When Voldemort discovered that the diary had been mutilated and robbed of all its powers, I am told that his anger was terrible to behold.

I do not think he understands why, Harry, but then, he was in such a hurry to mutilate his own soul, he never paused to understand the incomparable power of a soul that is untarnished and whole.

Dumbledore gone," whispered Mr. Weasley, but Mrs. Weasley had eyes only for her eldest son; she began to sob, tears falling onto Bill’s mutilated face.

Yet it fitted: Lord Voldomort has seemed to grow less human with the passing years, and the transformation he had undergone seemed to me to be only explainable if his soul was mutilated beyond the realms of what we might call ’usual evil’ …."